xml question regarding document comparing

From: "S.Watts" <denniswatts2000@home.com>

To: xml-dev@lists.xml.org

Date: Mon, 02 Jul 2001 13:07:42 -0700

I have 3 documents from different companies which are their versions
of a legal document or rule. I also have this official rule from a
governing body which needs to reflect the changes each company has put
forward. I would like to turn each version into a xml document so I
can realize the differences each version has from the official rule.
So I would like to create a master xml and compare it with one of the
versions. After the two are compared the master xml needs to contain
the changes that were made. I would like to create something that
would accomplish this rather than purchase something that would do
this for me. I would appreciate any help you could offer that would
help me accomplish this, thanks.
dennis watts
denniswatts2000@home.com